New mural by artist Scottie Marsh

While marathon racing only started in 1896 at the Olympic Games in Athens, long distance running is considered a human skill developed over a million years ago. Indigenous Australians, the San people of Southern Africa and the Tarahumara of Mexico hunted by running down an animal over several hours to days.

Humans have evolved to have the capacity to run for a very long way, very often, during their lifetime. It is an utterly inspiring activity and brings joy through suffering to almost every single person who has ever run a long distance, particularly when outside of their comfort zone.


We seem to have lost the wisdom around nutrition through the generations. At Running Science over the years, we’ve seen a growing issue of people relying on gels, lollies, goo, chews and the like for fuel. Scientific studies and marketing hype has convinced us that gels will give us the rocket fuel we need to achieve the impossible. But the truth is, it’s not that simple.

Yes, gels and goos provide energy in a convenient form. But do you need them?

First, the science

Dr Google will rightly inform you that a human’s glycogen stores will deplete faster than they can be replenished during a marathon. Glycogen, a super fuel crucial for keeping our muscles firing, is stored in the liver and muscles. It becomes depleted during long sessions, or runs when you’re working at max effort.

Converting stored glycogen into energy is a complex chemical reaction involving the metabolism of sugars with oxygen to power muscle contractions. Run out of sugar or oxygen and you’ll hit a point of exhaustion known as ‘bonking’. It’s like running out of petrol in a car – sudden, abrupt and will create the overwhelming desire to lie down in the middle of the marathon and go for a big fat sleep.

Makers of running fuels will argue that by replenishing your stores mid-run you can keep going hard for longer.

So, should you refuel during a race?

The short answer is yes, most likely. If you look at the elite runners, the majority, if not all, are refuelling through drinks, gels, energy bars etc. Our issue is not with gels, as such, but with the additives some of them contain, and the marketing and advice behind them. Simply put, there’s no one-size-fits-all solution and they aren’t a Band Aid solution for lack of training and bad diet.

Do you need a serve of fuel five minutes before a race and every forty minutes afterwards? For a four-hour marathon runner, that’s six serves per race. You begin to see why the marketing department tells you that you need them, not only for races but for every long run in the lead-up.

We’ve seen runners trying to stick to the recommended carb intake on the package and throw up. We’ve seen people try something new on race day and suffer for it (guilty of this)!

Our advice is:

  1. Pay attention to the ingredient list: We’re brand agnostic and don’t sell sports fuel in the shop, but would argue that you should look for something that’s more natural such as Maurten, that contains no colorants or preservatives.
  2. Experiment, experiment and experiment: Don’t learn the lesson during your race that a certain chew or gel doesn’t sit well with you. Firstly, toilets are few and far between on a race course and secondly it won’t be a fun race experience.
  3. Aim for glycogen adaptation: By training your body to run longer distances with less fuel, you can optimise your performance.

What is glycogen adaptation?

Glycogen adaptation is a key factor in marathon training and getting race-ready. It’s important to understand the role of glycogen as part of your marathon preparation, and how to adapt your nutrition and exercise strategy to maximize its benefits.

As you ramp up the intensity and duration of your workouts, your body becomes more efficient at using glycogen for energy. This process of adaptation enables you to sustain a higher level of performance over longer periods of time.

Nutritional advice for humans

Now, to be able to increase the intensity and duration of your workouts (i.e. increase mileage and pace) without injury, your body should be recovering from each session.

Your grandmother (or doctor) will tell you that to live a long, healthy life you need to eat a well balanced, nutritious diet. So, as a runner preparing for your first or fifteenth marathon? You need to eat a well balanced, nutritious diet.

What does this look like? Beyond the vegetables, proteins and complex carbohydrates you no doubt already know about, we would argue that it’s an intuitive process. Forget about weighing your chicken breast and quinoa salad for a moment. Listen to your body. If you do a long run on Sunday and wake up feeling like a train has run over you on Monday, perhaps you didn’t eat enough (or well enough) to recover. On the other hand, if you wake up feeling energised and ready to run again, then make a note of what you ate and experiment with similar approaches to identify trends.

A note on sleep

Elite runner Eliud Kipchoge sleeps eight hours a night, and naps two hours a day when preparing for marathons. Studies have shown that to reap the maximum benefit from training and to recover adequately, you need good quality sleep and a lot of it. In our hyper-connected society, you may need more sleep than you’re currently getting to reap the maximum rewards.

Our point is, you don’t need the peddlers of high-additive products telling you how to do nutrition. Aside from the physical training sessions you undertake in the weeks and months leading up to your marathon race, you have the power to listen to your body’s reactions and adaptations to food.

Need guidance on how to train for your next marathon? Book in for our special marathon training package